|MadSci Network: Physics|
A magnetic field can only be created by an electric current. It is possible to convert light into electric energy (e.g. in a solar cell) and use this to create a magnetic field. It is also possible to convert light into kinetic energy, but to create a magnetic field from that, you have to convert movement into electric energy again (e.g. by turbine or generator, which moves a conductor in a static magnetic field - is that what you meant by "armature"?). It is worthwhile to note that light is a very high-frequency electromagnetic wave and as such has a magnetic component. I do not know any application of that magnetic field directly, though. Greetings, Frank
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